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Potassium in graphite shows distinctive reducing properties towards carbonyls. The reaction products can be related to a mechanism similar to electrochemical reduction. The steric orientation of the reduction can be explained by the particular structure of potassium-graphite.Chromic anhydride in graphite offers a new selective method of preparation of aldehydes from the corresponding primary alcohol. This method is characterized by its specificity, high yields and a simple experimental procedure.Le potassium insert dans le graphite presente des proprietes rtductrices particulieres. Les produits de reduction peuvent &tre expliques par un mecanisme de type electrochimique. La stkrkochimie de la reduction s'explique par la structure du potassium-graphite.L'anhydride chromique insere dans le graphite offre une nouvelle methode d'oxydation selective des alcools primaires en aldehydes. Cette methode est caracttrisee par sa specificite et la simplicite des operations.

ether methyl and/or ring substitution under the reaction conditions. When the product mixture from a toluene-anisole chlorination is treated with ethanolic KOH at rooin temperature, one of the product peaks is completely converted to a new gas chromatographic peak of longer retention time, while a peak with the same retention time as benzyl chloride is converted to a material of the same retention time as benzyl ethyl ether at a much slower rate. Treatment of the product mixture with aqueous silver nitrate results in rapid loss of the same peak as above and the formation of material of the same retention time as phenol and the formation of material of the same retention time as formaldehyde. These qualitative results are consistent with the presence of chloromethyl phenyl ether in the product mixture (cf. ref. 5). In addition, a trace of material with the same retention time as a mixture of chloroanisoles was noted. These results strongly suggest that related reactions also occur with p-methylanisole. That this is so was demonstrated by mixing a product mixture with alcoholic KOH. Within 10 min after mixing, one product gas chromatographic peak had been destroyed and a new peak had appeared. A second peak was also destroyed with concomitant formatioil of another at a rate slower than the first. It is clear that p-methoxytoluene is destroyed by processes competitive with benzylic hydrogen abstraction.Using the value obtained in this work for p-phenoxytoluene and the previously unknowil value for p-fluorotoluene (Table I), along with the values reported previously by one of us (3), the following correlations2 were obtained: log k / k , = -0 . 7 6~ -.00; s, 0.045; r, 0.983; log k/ko = -0.60o' -.06; S, 0.073; r, 0.954.Including the values for nz-and p-nitrotoluene (1) Sodium borohydride reacts with sulfur at room temperature in the presence of appropriate organic solvents to give a sulfurated borohydride: NaBH2S3. The formulation of this hydride has been established by infrared, nuclear magnetic resonance, and elementary analysis. Thermal deco~nposition and hydrolysis are reported. The reaction observed with NaBH, appears to be general between borohydridcs and the lower elements of Group VIA: Se and Te. A facile preparative method of NaBH,S, is presented.

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b) Fro111 14~-Hydr0per0~y-A~~-androstene-3~-oI-I ?' -one 3-Monoacetate (20) A solution of 2a (100 mg) in pyridine (1.0 ml) containing triethylphosphite (0.5 ml) was heated on the steam bath for 15 mins and then evaporated under an air draft. The residue was crystallized twice from acetone-hexane as colorless plates, m.p. 162-163"; undepressed on admixture with 3 described under (a); h,,,(EtOH) 212 mp (E 8000); [aIDz6 + 104.2'. The mobility on thin-layer chromatography and the infrared spectrum of the product were identical with that of 3 prepared by the literature procedure (2b).